KR20160022349A

KR20160022349A - Method and apparatus for advanced temporal residual prediction in three-dimensional video coding

Info

Publication number: KR20160022349A
Application number: KR1020167001216A
Authority: KR
Inventors: 지쳉 안; 카이 장; 지안리앙 린
Original assignee: 미디어텍 싱가폴 피티이. 엘티디.
Priority date: 2013-07-16
Filing date: 2014-07-10
Publication date: 2016-02-29
Also published as: KR101763083B1

Abstract

A method and apparatus for three-dimensional or multi-view video coding using advanced temporal residual prediction is disclosed. The method determines the corresponding block in the temporal reference picture in the current subordinate view for the current block. The reference residual for the corresponding block is determined according to the current motion or disparity parameters. The predictive encoding or decoding is then applied to the current block based on the reference residual. When the current block is coded using disparity compensated prediction (DCP), the reference residual is used as a predictor for the current residual generated by applying the DCP to the current block. The current block may correspond to a prediction unit (PU) or a coding unit (CU).

Description

METHOD AND APPARATUS FOR ADVANCED TEMPORAL RESIDUAL PREDICTION IN THREE-DIMENSIONAL VIDEO CODING BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

Cross reference to related applications

The present invention is related to PCT patent application Serial No. PCT / CN 2013/079468, filed on July 16, 2013, entitled " Methods for Residual Prediction ", filed on November 14, 2013, PCT Patent Application Serial No. PCT / CN2013 / 087117 entitled " Apparatus for Residual Prediction in Three-Dimensional Video Coding ". PCT patent applications are hereby incorporated by reference in their entirety.

The present invention relates to three-dimensional and multi-dimensional video coding. More particularly, the present invention relates to video coding using temporal residual prediction.

Three-dimensional (3D) televisions were the latest technology trends intended to bring viewers a fantastic viewing experience. Various technologies have been developed to enable 3D viewing. Multi-view video is a key technology for 3DTV applications among other things. Conventional video is a two-dimensional (2D) medium that provides viewers with only a single view of the scene from a camera's point of view. Multi-view video, however, can provide any viewpoint of dynamic scenes and can provide viewers with sensation of realism. The 3D video formats also include depth maps that are associated with corresponding texture images. Depth maps should also be coded to render 3D video or multiple views.

Various techniques for improving the coding efficiency of 3D video coding are disclosed in the art. There are also activities to standardize coding techniques. For example, a working group (ISO / IEC JTC1 / SC29 / WG11) within the International Organization for Standardization (ISO) is developing High Efficiency Video Coding (HEVC) (so called 3D HEVC) based on 3D video coding standards. To reduce inter-view redundancy, a technique called disparity-compensated prediction (DCP) has been added as an alternative coding tool to motion-compensated prediction (MCP) . The MCP is also referred to as inter picture prediction using previously coded pictures of the same view in different access units (AUs), while the DCP uses the already coded pictures of other views in the same access unit Quot; inter-picture prediction ".

For 3D HEVC, advanced residual prediction (ARP) methods have been disclosed to improve the efficiency of inter-view residual prediction (IVRP), where the motion of the current view is applied to the corresponding block of the reference view. In addition, additional weighting factors are introduced to compensate for quality differences between different views. Figure 1 illustrates an exemplary structure of advanced residual prediction (ARP) as disclosed in 3D HEVC where the time for the current block 112 (i.e., inter-time) residuals (190) is predicted using the reference temporal residual (170) to form a new residual (180). The residual 190 corresponds to a temporal residual signal between the current block 110 and the temporal reference block 150 of the same view. View 0 represents the base view and View 1 represents the dependent view. The procedure is described below.

1. The estimated DV 120 for the current block 110 referring to the inter-view criteria is derived. This inter-view criteria, represented as the corresponding picture (CP), is in the base view and has the same POC as that of the current picture in view 1. The corresponding region 130 of the corresponding picture for the current block 110 in the current picture is positioned according to the estimated DV 120. The reconstructed pixel of the corresponding region 130 is denoted as S.

2. A reference corresponding picture of the base view with the same POC as that of the reference picture for the current block 110 is found. The MV 160 of the current block is used for the corresponding region 130 to position the reference corresponding region 140 in the reference corresponding image whose relative displacement to the current block is DV + MV. The reconstructed image of the reference corresponding image is known as Q.

3. The reference residual 170 is calculated as RR = S-Q. The operation is sample-wised, that is, RR [j, i] = S [j, i] -Q [j, i], where RR [j, i] [j, i] is the sample of the corresponding region 130, Q [j, i] is the sample of the reference corresponding region 140, and [j, i] is the relative position of the region. In the following description, all operations on the area are sample-wise operations.

4. The reference residual 170 will be used as the residual prediction for the current block to generate the final residual 180. [ Further, the weighting factor may be applied to the reference residual to obtain a weighted residual for prediction. For example, three weighting factors, 0, 0.5, and 1, may be used in the ARP, where 0 implies that no ARP has been used.

The ARP process is applicable only to blocks using motion compensated prediction (MCP). For blocks using disparity compensated prediction (DCP), no ARP is applied. It is desirable to develop a residual prediction technique that is also applicable to DCP coded blocks.

A method and apparatus for three-dimensional or multi-view video coding using advanced temporal residual prediction is disclosed. The method determines the corresponding block of the temporal reference picture of the current subordinate view for the current block. The reference residual for the corresponding block is determined according to the current motion or disparity parameters. The predictive encoding or decoding is then applied to the current block based on the reference residual. When the current block is coded using disparity compensated prediction (DCP), the reference residual is used as a predictor for the current residual generated by applying the DCP to the current block. The current block may correspond to a prediction unit (PU) or a coding unit (CU).

The corresponding block of the temporal reference picture may be positioned based on the current block using a derived motion vector (DMV) and the DMV corresponds to a selected motion vector of the reference block selected in the reference view. The selected reference block can be positioned from the current block using MV, DV (disparity vector), or DDV (derived DV) of the current block. The DDV may also be derived according to an adaptive disparity vector derivation (ADVD) and the ADVD is derived based on one or more temporal neighbor blocks and two spatial neighbor blocks. The two spatially neighboring blocks are positioned at the above-left position and the left-bottom position of the current block. Temporally neighboring blocks may correspond to one aligned temporal reference block and one collocated temporal reference block of the current block and the aligned temporal reference block may correspond to a temporal reference picture from the current block using the scaled MV, As shown in FIG. The default DV may be used if either the temporal neighbor block or the spatial neighbor block is not available. The ADVD technique may also be applied to conventional ARPs to determine the corresponding block in the inter-view reference picture of the reference view for the current block.

The DMV is scaled to a first temporal reference picture based on the reference list reference index or the selected reference picture in the reference list. The first temporal reference picture or the selected reference picture is then used as the temporal reference picture of the current dependent view of the current block. The DMV can be set to the motion vector of the spatial neighboring block or the temporal neighboring block of the current block. The DMV can be explicitly signaled as a bitstream. When DMV is zero, the corresponding block of the temporal reference picture corresponds to the colocated bock of the current block.

The flags can be flagged for each block to control the weighting factors associated with the predictive encoding or decoding of the current block based on on, off, or reference residuals. The flags can be explicitly signaled as a sequence level, a view level, a picture level or a slice level. The flag may also be inherited in merge mode. The weighting factor may correspond to 1/2.

Figure 1 illustrates an exemplary structure of an advanced residual prediction where current inter-time residuals are predicted in the view direction using reference inter-time residuals according to 3D HEVC.
FIG. 2 illustrates a simplified diagram of an advanced temporal residual prediction according to an embodiment of the present invention, wherein the current inter-view residual is predicted in the time direction using the reference inter-view residual.
Figure 3 illustrates an exemplary structure of an advanced temporal residual prediction according to an embodiment of the present invention, wherein the current inter-view residual is predicted in the temporal direction using a reference inter-view residual.
Figure 4 illustrates an exemplary process for determining a motion vector derived to position a temporal reference block of a current block.
Figure 5 illustrates two spatial neighbor blocks used to derive a disparity vector candidate or a motion vector candidate for adaptive disparity vector derivation (ADVD).
Figure 6 illustrates aligned disparity vector candidates or motion vector candidates for aligned temporal DV (ATDV).
Figure 7 illustrates an exemplary flow chart of advanced temporal residual prediction in accordance with an embodiment of the present invention.
Figure 8 illustrates an exemplary flow diagram of advanced residual prediction using adaptive disparity vector derivation (ADVD) to determine corresponding blocks of an inter-view reference picture in a reference view in accordance with an embodiment of the present invention.

It will be readily appreciated that the components of the present invention, as generally described and illustrated in the drawings herein, can be arranged and designed in a wide variety of different configurations. Accordingly, the following more detailed description of embodiments of the systems and methods of the present invention, as set forth in the drawings, is not intended to limit the scope of the invention as claimed, but rather to include selected embodiments of the invention It just represents.

Reference throughout this specification to "one embodiment," "an embodiment, " or similar language, means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the invention do. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. However, those skilled in the art will recognize that the invention may be practiced without one or more of the specific details, or with other methods, components, or the like. In other instances, well-known structures or operations are not described or shown in detail in order to avoid obscuring aspects of the present invention.

The illustrated embodiments of the present invention will be best understood with reference to the drawings, wherein like parts are designated by like numbers throughout the figures. The following description is merely exemplary in nature and is merely illustrative of certain selected embodiments of apparatus and methods consistent with the invention claimed herein.

To improve the performance of a 3D coding system, the present invention discloses an advanced temporal residual prediction (ATRP) technique. In ATRP, at least some of the motion or disparity parameters of a current block (e.g., a prediction unit (PU) or coding unit (CU)) are temporally Is applied to the corresponding block of the reference picture. The corresponding block of the temporal reference picture is positioned by the derived motion vector (DMV). For example, the DMV may be a motion vector (MV) of a reference block that is pointed by the current DV in the reference view. A simplified exemplary ATRP process is illustrated in FIG.

In Figure 2, the current block 210 of the current picture is a disparity compensated prediction (DCP) coded block with a disparity vector 240. The derived motion vector (DMV) 230 is used to locate the temporal reference block 220 of the temporal reference picture, where the current picture and the temporal reference picture are in the same reference view. The disparity vector 240 of the current block is used as the disparity vector 240 'of the temporal reference block. By using the disparity vector 240 ', the inter-view residual of the temporal reference block 220 can be derived. The inter-view residuals of the current block 210 may be predicted from the temporal direction by the inter-view residuals. Although the disparity vector DV of the current block 210 is used by the temporal reference block 220 of the current block to derive the inter-view residual for the temporal reference block 220, other motion information (e.g., A motion vector (MV) or an induced DV) may also be used to derive inter-view residuals for the temporal reference block 220.

Figure 3 illustrates an example of an ATRP structure. View 0 represents the same base view as the base view, and View 1 represents the dependent view. The current block 312 in the current picture 310 of view 1 is coded. The procedure is described as follows.

1. The estimated MV 320 for the current block 310 referring to the inter-time (i.e., temporal) reference is derived. The inter-time reference displayed as the corresponding picture is in view 1. The corresponding region 330 of the corresponding picture is positioned relative to the current block using the estimated MV. The reconstructed samples of the corresponding region 330 are known as S. A corresponding region is a region having the same image unit structure as a current block (for example, a macro block (MB), a prediction unit (PU), a coding unit (CU), or a transform unit )). Nevertheless, the corresponding region may also have a different image unit structure than the current block. The corresponding region may also be larger or smaller than the current block. For example, the current block corresponds to the CU and the corresponding block corresponds to the PU.

2. An inter-view reference picture of the reference view for the corresponding area with the same POC as the POC of the corresponding picture of view 1 is found. The same DV 360 'as that of the current block is used to position the inter-view reference block 340 (denoted Q) in the inter-view reference image of the reference view for the corresponding block 330 And the relative displacement between the reference block 340 and the current block 310 is MV + DV. The reference residual in the time direction is derived as (S-Q).

3. The reference residual in the temporal direction will be used for encoding or decoding the residual of the current block to form the final residual. Similar to ARP, a weighting factor can be used for ATRP. For example, the weight factor may correspond to 0, 1, 2, and 1, where 0/1 implies that ATRP is off / on.

An example of the derivation of DMV is illustrated in Fig. The current MV / DV or derived DV 430 is used to locate the reference block 420 of the reference view corresponding to the current block 410 of the current view. The MV 440 of the reference block 420 may be used as the derived MV 440 'for the current block 410. An exemplary procedure for deriving DMV is shown below (referred to as DMV Derivation Procedure 1).

- Add the current MV / DV or DDV (derived DV) of the list X (X = 0 or 1) to the intermediate position (or other positions) of the current block (eg PU or CU) to obtain the sample position We found a reference block covering the sample position in the reference view.

When the reference picture of the list X of the reference block has the same picture order count (POC) as one reference picture of the current reference list X,

Set the DMV to the MV of the list X of the reference block;

- Otherwise,

When the reference image of the list 1-X of the reference block has the same POC as one reference image of the current reference list X,

• Set the DMV to the MV of the list 1-X of the reference block;

- Otherwise,

● Set the DMV to a default value such as (0, 0) to point to the temporal reference picture of list X with the minimum reference index.

Alternatively, DMV may also be derived as follows (referred to as DMV derivation procedure 2).

Add the current MV / DV or DDV of the list X to the intermediate position of the current PU to acquire the sample position and find the reference block covering the sample position in the reference view.

When the reference picture of the list X of the reference block has the same POC as one reference picture of the current reference list X,

Set the DMV to the MV of the list X of the reference block;

- Otherwise,

Set the DMV to a default value such as (0, 0) to point to the temporal reference image of list X with the minimum reference index.

In the above two examples of the DMV derivation procedure, the DMV may be scaled to a first temporal reference picture (from the reference index view) of the reference list if the DMV points to another reference picture. Any MV scaling technique known in the art can be used. For example, MV scaling may be based on a picture order count (POC) distance.

In another embodiment, adaptive disparity vector derivation (ADVD) is disclosed to improve ARP coding efficiency. In ADVD, the three DV candidates are derived from temporal / spatial neighbor blocks. Only two spatial neighbors 520 and 530 of the current block 510 are examined as shown in FIG. The new DV candidate is inserted into the list only if it is not already the same as any DV candidate in the list. If the DV candidate list is not fully populated after using neighboring blocks, default DVs will be added. The encoder can determine the best DV candidate to be used in the ARP according to the RDO criterion and signal the index of the selected DV candidate to the decoder.

For further improvement, the aligned temporal DV (ATDV) is disclosed as an additional DV candidate. The ATDV is obtained from the aligned block positioned by the scaled MV for the colocated picture as shown in FIG. Two colocated images are utilized, which can also be used in NBDV derivation. ATDV is checked prior to DV candidates from neighboring blocks when it is used.

The ADVD technique can be applied to ATRP to find induced MVs. In one example, the three MV candidates are derived for ATRP similar to the three DV candidates derived for ARP in ADVD. The DMV is placed in the MV candidate list if DMV is present. The spatially / temporally neighboring blocks are then examined to find more MV candidates similar to the process of finding a merging candidate. Also, only two spatial neighbors are examined as shown in FIG. If the MV candidate list is not fully populated after using neighboring blocks, then default MVs may be added. The encoder can find the best MV candidates used in ATRP and signal the index to the decoder, similar to that done in ADVD for ARTP.

A system that includes new advanced residual prediction (ARP) in accordance with embodiments of the present invention is compared to a conventional system according to conventional ARP (3D-HEVC test model version 8.0 (HTM 8.0)). The system configuration according to embodiments of the present invention is summarized in Table 1. Conventional systems allow both ADVD, ATDV, and ATRP to be set to Off. The results for Tests 1 to 5 are listed in Tables 2 to 6, respectively.

The performance comparison is based on the set of different test data listed in the first column. BD rate differences are shown for texture images in view 1 (video 1) and view 2 (video 2). A negative value of the BD rate implies that the present invention has better performance. As shown in Tables 2 to 6, the system including embodiments of the present invention show a significant BD rate reduction of 0.6% to 2.0% for View 1 and View 2. The coded video PSNR for the video bit rate, the coded video PSNR for the total bit rate (texture bit rate and depth bit rate), and the BD rate measurement for the synthesized video PSNR for the total bit rate, (0.2% -0.8%). The coding time, decoding time, and rendering time are only slightly higher than conventional systems. However, the encoding time for test 1 increases by 10.1%

Figure 7 illustrates an exemplary flow diagram for a three-dimensional or multi-view video coding system using advanced temporal residual prediction (ATRP) in accordance with an embodiment of the present invention. The system receives the input data associated with the current block of the current picture in the current subordinate view, as shown in step 710, where the current block is associated with one or more current motion or disparity parameters. The input data may correspond to uncoded or coded texture data, depth data, or associated motion information. The input data may be retrieved from a store, such as a computer memory, a buffer (RAM or DRAM) or other media. The input data may also be received from a processor, such as a controller, a central processing unit, a digital signal processor, or electronic circuits that derive input data. The corresponding block of the temporal reference picture in the current subordinate view is determined for the current block as shown in step 720. [ The reference residual for the corresponding block is determined according to the one or more current motion or disparity parameters as shown in step 730. [ Predictive encoding or decoding is applied to the current block based on the reference residual as shown in step 740. [

Figure 8 illustrates an exemplary flow diagram for a three-dimensional or multi-view video coding system using adaptive disparity vector derivation (ADVD) for advanced residual prediction (ARP), in accordance with an embodiment of the present invention. The system receives the input data associated with the current block of the current picture in the current subordinate view, as shown in step 810. [ The corresponding block of the inter-view reference picture of the reference view for the current block is determined in step 820 using the DDV (derived DV) of the current block. The first temporal reference block of the current block is determined in step 830 using the first motion vector of the current block. The second temporal reference block of the corresponding block is determined using the first motion vector in step 840. The reference residual for the corresponding block is determined in step 850 from the first temporal reference block and the second temporal block. The current residual is determined from the current block and the corresponding block in the inter-view reference picture at step 860. [ The encoding or decoding is applied to the current residual based on the reference residual in step 870, where the DDV is derived according to an adaptive disparity vector derivation (ADVD), and the ADVD is determined based on two spatial neighbor blocks of the current block and one or more temporal Are derived based on neighboring blocks, and the two spatially neighboring blocks are positioned at the upper right position of the current block and the lower left position.

The flowcharts shown above are intended to illustrate examples of three-dimensional or multi-view video coding systems using advanced temporal residual prediction or advanced residual prediction in accordance with embodiments of the present invention. Skilled artisans may modify each step, rearrange the steps, split the steps, or combine the steps to practice the invention without departing from the spirit of the invention.

The previous description is set forth to enable those skilled in the art to practice the invention as provided in the context of a particular application and its requirements. Various modifications to the described embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments. The present invention, therefore, is not intended to be limited to the specific embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. In the foregoing specification, various specific details are set forth in order to provide a thorough understanding of the present invention. Nevertheless, it will be understood by those skilled in the art that the present invention may be practiced.

The pseudo residual prediction and DV or MV estimation methods described above can be used in a video encoder as well as a video decoder. Embodiments of the pseudo residual prediction methods according to the present invention as described above may be implemented with various hardware, software codes or a combination of the two. For example, embodiments of the present invention may be program code integrated into video compression software to perform the processing described herein, or circuitry integrated into a video compression chip. Embodiments of the present invention may also be program code executing on a Digital Signal Processor (DSP) to perform the processing described herein. The present invention may also include a number of functions performed by a computer processor, a digital signal processor, a microprocessor, or a field programmable gate array (FPGA). These processors may be configured to perform certain tasks in accordance with the present invention by executing machine readable software code or firmware code that defines specific methods to be implemented by the present invention. The software code or firmware code may be developed in different programming languages and in different formats or styles. The software code may also be compiled for different target platforms. However, the different code formats, styles and languages of the software codes and other means of configuring the code to carry out the tasks according to the invention will not depart from the spirit and scope of the invention.

The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The described examples are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is accordingly indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

A method for three-dimensional or multi-view video coding,
The method comprising: receiving input data associated with a current block of a current picture in a current dependent view, the current block being associated with one or more current motion or disparity parameters; ,
Determining a corresponding block in the temporal reference picture in the current subordinate view for the current block,
Determining a reference residual for the corresponding block according to the one or more current motion or disparity parameters;
Applying predictive encoding or decoding to the current block based on the reference residual;
Lt; RTI ID = 0.0 > and / or < / RTI > multi-view video coding.

The method according to claim 1,
Wherein a corresponding block in the temporal reference picture is positioned based on the current block using a derived motion vector (DMV).

3. The method of claim 2,
Wherein the DMV corresponds to a selected motion vector of a selected reference block in a reference view.

The method of claim 3,
Wherein the selected reference block is positioned from the current block using MV, DV (disparity vector), or DDV (derived DV) of the current block.

5. The method of claim 4,
Wherein the DDV is derived according to an adaptive disparity vector derivation (ADVD), the ADVD is derived based on one or more temporal neighbor blocks and two spatial neighbor blocks, and the two spatially neighboring blocks are located on the upper right is positioned at the position of the above-right and left-bottom positions.

6. The method of claim 5,
Wherein the one or more temporal neighbor blocks correspond to one aligned temporal reference block and one collocated temporal reference block of the current block and the aligned temporal reference block uses the scaled MV to determine the current Wherein the temporal reference picture is positioned within the temporal reference picture from the block.

6. The method of claim 5,
Wherein the default DV is used if no DV of the one or more temporal neighbor blocks and the two spatially neighboring blocks is available.

The method of claim 3,
Wherein the default MV is used as a DMV when the selected MV of the selected reference block in the reference view is not available and the default MV is a zero MV with a reference picture index equal to zero. Lt; / RTI >

3. The method of claim 2,
The DMV is scaled for a first temporal reference picture based on a reference index of a reference list or a selected reference picture of the reference list and the first temporal reference picture or a selected reference picture is scaled for a current temporal reference picture Wherein the temporal reference picture is used as a temporal reference picture.

3. The method of claim 2,
Wherein the DMV is set to one motion vector of a spatial neighbor block or a temporal neighbor block of the current block.

3. The method of claim 2,
RTI ID = 0.0 > DMV < / RTI > is explicitly signaled as a bitstream.

The method according to claim 1,
Wherein a corresponding block in the temporal reference picture corresponds to a collocated block in which a derived motion vector (DMV) is equal to zero.

The method according to claim 1,
Wherein the current block of the current picture in the current subordinate view is coded using disparity compensated prediction (DCP) to form a current residual of the current block.

14. The method of claim 13,
Wherein a reference residual is used to predict a current residual of the current block.

The method according to claim 1,
Wherein the flag is signaled for each block to control an on, off or weighting factor associated with the predictive encoding or decoding of the current block based on the reference residual. Way.

16. The method of claim 15,
Wherein the flag is explicitly signaled as a sequence level, a view level, a picture level, or a slice level.

16. The method of claim 15,
Wherein the flag is inherited in a merge mode. &Lt; Desc / Clms Page number 22 >

16. The method of claim 15,
Wherein the weighting factor corresponds to one-half.

The method according to claim 1,
Wherein the current block corresponds to a prediction unit (PU) or a coding unit (CU).

An apparatus for three-dimensional or multi-view video coding,
Comprising one or more electronic circuits,
The one or more electronic circuits,
Receiving a current block of a current picture in a current subordinate view, the current block being associated with one or more current motion or disparity parameters;
Determining a corresponding block in the temporal reference picture in the current subordinate view for the current block,
Determine a reference residual for the corresponding block according to the one or more current motion or disparity parameters,
And to apply predictive encoding or decoding to the current block based on the reference residual.

A method for three-dimensional or multi-view video coding,
Receiving input data associated with a current block of a current picture in a current subordinate view;
Determining a corresponding block in an inter-view reference picture in a reference view for the current block using a derived DV of the current block;
Determining a first temporal reference block of the current block using a first motion vector of the current block,
Determining a second temporal reference block of the corresponding block using the first motion vector,
Determining a reference residual for the corresponding block from the first temporal reference block and the second temporal reference block,
Determining a current residual from the current block and a corresponding block in the inter-view reference picture;
And applying predictive encoding or decoding to the current residual based on the reference residual,
Wherein the DDV is derived according to an adaptive disparity vector derivation (ADVD), wherein the ADVD is derived based on one or more temporal neighbor blocks and two spatial neighbor blocks of the current block, The position of the top right corner of the block and the position of the bottom left corner of the block.